Unsaturated halogen-containing



Reissued Aug. 14, 1951 UNSATURATED HALOGEN-CONTAINING NITRO COMPOUNDSAND THEIR PRO- DUCTION Eduard Cornelis Kooijman and Johan overhofi,

Amsterdam,

Netherlands, assignors to Shell Development-Company, San Francisco,Calif., a

corporation of Delaw No Drawing. Original 14, 1949, Serial No. 739,948,April 7,

reissue May 8, 1951, Serial No.

plication for are No. 2,473,341, dated June 2Z5,259. In the NetherlandsJuly. 5, 1946 (Cl. 260-644) Matter enclosed in heavy brackets I: IIappears in the original patent but forms no part of this 19 Claims.

reissue specification; matter printed in italics in This inventionrelates to the production ,of new and useful unsaturatedhalogen-containing ultra-compounds, and more specifically relates to thenitration of halogen-containing olefinic compounds, and to thehalo-nitro-oleflnic compounds thereby produced.

According to the process of the present invention, olefinic halogencompounds of the general formula:

wherein R1, R2, R3, R4, R5 and Rs represent hydrogen atoms, hydrocarbonradicals, or halo-substituted hydrocarbon radicals, such as alkyl,aralkyl, alkaryl, aryl, or cyclic parafiinic radicals, or theirhalo-substitution products, and wherein X represents a halogen atom, aresubjected to the action of nitrous acid, or nitrogen oxides, underconditions hereinafter described, to produce new and useful compounds.The re-. actants of the present invention, therefore, areolefinichalides wherein the olefinic linkage is in the beta, gamma position withrespect. to the halogen atom, and the beta carbon atom is an unsaturatedtertiary carbon atom. In view of the diminution in the chemicalreactivity of olefinic linkages caused by a multiplicity of carbonatoms, reactants containing not more than about 16 carbon atoms, whichare open chain monoolefinic halohydrocarbons containing the structuralgroupin I i on (halogen) C- IO: U comprise the most suitable class ofolefinic halide reactants for employment in the process of theinvention. It is essential that the structure and composition of thereactants employed in the process of our invention be within theselimitations. We prefer to employ a reactant wherein the unsaturatedgamma carbon atom, as above defined, is the carbon atom of a terminalmethylene group, and wherein the halogen atom is a chlorine or bromineatom, since, as we have found, excellent results are achieved therewith,i. e., relatively high yields and rates of production are obtainedtherewith, and the products dicates the additions made by reissue.

obtained are especially advantageous for a variety of uses. In the abovestructural formula, suitable alkyl radicals which R1, R2, R3, R4, R5 andHe may represent are, for example, the methyl, ethyl, npropyl,isopropyl, the butyl, and the amyl radicals; suitable aralkyl radicalsare, for example, the benzyl, methyl benzyl, phenyl ethyl, phenylpropyl, and naphthyl methyl radicals; suitable alkaryl radicals are, forexample, the methyl phenyl, ethyl phenyl, propyl phenyl, methyl naphthyland ethyl naphthyl radicals; suitable aryl radicals, for example, arethe phenyl and naphthyl radicals; and suitable representativecycloparafiinic or cycloaliphatic hydrocarbon radicals are thecyclopentyl, methyl cyclo pentyl, dimethyl cyclopentyl, ethylcyclopentyl, cyclohexyl, methyl cyclohexyl, polymethyl cyclohex l, andpropyl cyclohexyl radicals. Representative halogen-substitutedhydrocarbon radicals which R1, R2, R3, R4, R5 and Rs may represent arethe chloromethyl, dichloromethyl, chloroethyl, bromomethyl, bromoethyl.chloropropyl, chlorobutyl, iodoethyl, fluoromethyl, chlorobenzyl,chlorophenyl, dichlorophenyl, chlorona'ohthyl, chlorocyclopentyl,bromocyclopentyl, chlorocyclohexyl, chloromethyl cyclopentyl andbromomethylcyclohexyl radicals.

[The new compounds of the present invention may be represented by thegeneral formula:

' wherein R1, R2, R3, R4. R5, R6 and X represent the same atoms or raicals as above described.-

Thus, the new compounds prepared according to the process of the pre entinvention are nitrohalo-olefinic com ounds wherein the olefinic'relation to both the nitro group and the halogen atom, which nitro groupand halogen atom are attached to different carbon atoms, and thereforeeach of the said different carbon atoms are attached to the sameunsaturated tertiary carbon atom. The compounds conforming in structureand composition to this definition have not been known heretoforeJ The[above described! compounds of the in-' which dissociates -into nitrogenvention may be employed for a Wide variety of applications of industrialand commercial importance. Thus, for example, such compounds may beemployed and are surprisingly eifective as fumigants against manyharmful insects, as selective extracting agents for a variety ofsubstances, as solvents, for example, of cellulose derivatives, in dyecompositions, in the preparation of pharmarceuticals, in varnish, dopeand lacquer compositions, in detergent compositions, as emulsifiers, asintermediates in the preparation of valuable derivatives and the like.

As above described, the new compounds 'oi lthe present invention areprepared by reacting a halogen-containing olefinic compound, as abovedefined, with nitrous acid or a nitrogen. oxide or mixture of oxides.The preferred process contemplates performing the reaction in an aqueone medium, for example, by dissolving 'or dispersing the olefinicreactant in an aqueous solution of a mineral acid, and adding thereto anaqueous solution of an alkali or alkaline earth metal nitrite. Thereaction between the nitrite and acid produces nitrous acid directly inthe reaction mixture, which then reacts with, or

oxides whiche eact with-the dissolved or dispersedolefinic compound.Various mineral acids which react with the nitritesto producenitrousacid may behemployed, sulfuric acid giving excellent results, as dophosphoric and nitric acids. The halogen acids suchas hydrochloridhowever, are less suit.- able,-since they may undergo side reactionswith the olei'inic reactant resulting in the formation of. undesiredadditive-compounds. Various modifications in the preferred process maybe made, e. -g.,-the-alkali oralkaline: earth. metal nitrites maybeadded to theacidified aqueous reaction mixture i-nsolidform, preferablypulverized in order -to achieve rapid reaction.

Incarrying out a preferred embodiment of the process of the invention,an olefinic compound of. thegeneral formula:

wherei'n'Ri, R2; R3, R4, R5 and Rs'representhw drogen atoms, hydrocarbonradicals orhalo-substitu'te'd hydrocarbon radicals, such as alkyl,aralkyl, 'alkaryl, 'arylor cyclic parafflnic groups, or theirhalo-substitution products, and wherein X represents a halogen atom, andpreferably wherein R1 and Rzare hydrogen atoms and X is a chlorine orbromine atom, may be dissolved or dispersed in an aqueous solution ofsulfuric acid. To this solution may be added an aqueous solution o'fanalkali'or alkaline earth metal nitrite; Thepr'eferred reactiontemperature i'sfrom about to 60 C., though lower temperatures, e; 'g., 0'C.,and'higher temperatures, 'e. g., 100C. may be used. "Temperatures ofabove about 100 (3., however, should be avoided, since undesirable sidereactionsmay occur "at such elevated temperatures. The unsaturatednitro-halo-olefinic products may be separated from the reactionmixture'by any convenient means,as for. example, by fractionaldistillation. We have found, however,'that during distillation aconsiderable quantity of .gases may be released from the reactionmixture, especially where the nitrite additionwas performe'datrelatively low temperatures, which may interfere with the distillationprocess. This nitrous acidt Part of. the

60 C1, the blue color rapidly changes to green.

We have further observed, as above described, that in. the recovery'ofour products by fractional distillation, there may be generated duringthe distillation-a considerable quantity of gas which may interfere withsaid distillation. This evolution/of gas is especially evident when thenitrite additionjwa's performed at relatvely low tem- .p'eratures, e.g., below about 40 C. Though we do no'twish't'o be limited by anytheoretical explanation, we believe these phenomena are due at least inpartto the formation of an addition product or products "between theolefin and the oxides of nitrogen, probably nitrogen trioxide, which areprobably formed from the generated attached nitrogen oxidesare ,splitoff by the elevated temperature encountered. during the reaction or thedistillation, thereby causing the color change and gas generation.

As illustrative of a specific example of a preferred embodiment of theprocess of the present invention, from-about 1 to-G .mols ofmethallylchloride (Z-chloromethylpropsne-l) isv dissolved or dispersedin an aqueous solution of sulfuric acid comprising from about 50 to moleof water and from about 1 to 10 mole of sulfuric acid. A quantity of an.aqueous solution of sodium nitrite, comprising about 1 part of nitriteto from about 1 to 10 parts of water, preferably sufficient 'to generatean excess of nitrous acid, is slowly added, thetemperature being held tofrom about25' to '60 C. The reaction products are washed with water,mixed with about double their volume of toluene, and heated to boilingtemperature. At the end of gas generation the toluenean'd unreactedmeth'all'yl chloride are removed by vacuum distillation and the desiredproducts recovered'by vacuum fractional distillation. If desired, theproduct may be further purified, for example by treatment with aqueousalkali, acidification and ether extraction. [The chief product obtainednitrop'ropene-ll] I "In'a'subst'antially identical manner, otherhaloencontaining'o'lefinic compounds or the above defined class m'aybe'treated to produce new and useful products. For example, the followingcompoundsma y be treated in accordance with the process of our invention[to produce unsaturated nitro compounds conforming to the abovedeflnition]: 2-bromomethylpropene-1; 3-chloro-2- methylbutene-l;3-chloro-2,3-dimethyibutene-1; 3 chloro 2 methylpentene-13-chloro-2methylhexene-l; "3-chlcro-2Pethylbutene-l; 3-chloro-2,3-diethylbutene-1; 3-chlo'ro-2-methyl-3-phenylbutene-l2-iodomethy1propane-1; 2-chloromethyl-4,4-dimethylpentene-1;2-chloromethyl- 4'-chlorobutene-1; and. their homologs, analogs, andsuitableproducts, such as:

As above described, we prefer to carry out our process in an aqueoussolution or dispersion by generating nitrous acid directly in thesolution.

However, variations in the described procedure may be made withoutdeparting from the scope of our invention. For example, a nitrogen oxidesuch as nitrogen trioxide, which may or may not be admixed with an inertgaseous diluent, may be introduced directly into the olefinic reactant,which may or may not be dissolved or dispersed in an aqueous ornon-aqueous solvent. A further modification is the vapor phase reactionbetween a vaporized olefinic reactant and a nitrogen oxide or mixture ofoxides which may or may not be admixed with an inert gaseous diluent.The process of the present invention may be operated batchwise,intermittently, or continuously, as is desired and convenient in anyspecific application. In the preferred process, or modificationsthereof, super or sub-atmospheric pressures may be employed, but we havefound that atmospheric pressure gives excellent results in mostinstances and is the preferred pressure.

As above described, the alkali and alkaline earth metal nitrites aregenerally suitable for use in the process of our invention. For example,sodium and potassium nitrites give excellent results, as do barium andstrontium nitrites. In some instances an insoluble precipitate may beformed, for example, when barium nitrite is used in conjunction withsulfuric acid insoluble barium sulfate is formed. However, this does notinterfere with the process of our invention, and

may be advantageous where removal of the me-' tallic ion is desired.

The following examples further illustrate preferred embodiments of ourinvention, which is not to be considered as limited thereby:

EXAMPLE I To a mixture of 2'70 grams of methallyl chloride, 392 grams ofsulfuric acid, and 1600 grams of water was added dropwise a solution of520 grams of sodium nitrite in 675 grams of water. The temperature washeld to about 40 C. during the nitrite addition, which required abouttwo hours. A blue color soon appeared in the oil layer, which at the endof the reaction contained the nitrosation products, any unconvertedmethallyl chloride, and a minor amount of by-products. The oil layer wasseparated'and washed with water. The separated oil layer, weighing 380grams, was mixed with a double quantity of toluene, and the resultingmixture heated to boiling temperature. The color rapidly changed fromblue to green or greenish-yellow, with evolution of some gas, probablychiefly nitrous oxide. When gas evolution ceased, the unreactedmethallyl chloride and subsequently the toluene were removed by vacuumdistillation, the residue turning yellow. The yellow residue, containingthe desired product and a minor amount of by-products, was subjected tofractional distillation. The fraction boiling at from 60 to C. at 10 mm.pressure was treated with a strong aqueous solution of lye, and theundissolved constituents separated therefrom by ether extraction. Thealkaline solution was acidifled, extracted with ether, andEZ-chloromethyl- B-nitropropene-l (nitromethallylchloride) ,1 thedesired productL] separated therefrom. The product was a pale yellowliquid with a boiling point of 62 C. at 4' mm. pressure, a refractiveindex n =1.4742, and a density of 1.234 at 20 C. The yield was about 50%based on the converted methallylchloride; omission of the alkalipurification step results in a yield of about 70%.

EXAMPLE II Example I was repeated at four other temperatures: 0, 10, 25and 60 C. Analogous results and substantially identical yields wereobtained, but as shown in the following table, more methallyl-. chloridereacted at the higher temperatures, but a correspondingly larger residueremained after fractionation.

Reaction Unconvcrtcd Residue Tempera- Methallylafter Fracture Chloridetionation G. Grams Grams 0 140 15 10 1-50 20 25 50 1 40 90 60 60 75 G5EXAMPLE W methyl-3-nitropropene-1] which comprises reacting, at atemperature of not more than about 100 C., methallyl-chloride withnitrous acid.

3. The process [for the production of 2-ch1oro 7 methyISmitropropene-ljl" which comprises reacting; at atemperature of not morethan about 100 C., methallyl-chloride in an aqueous-medium with nitrousacid.

4-. The'process [for theproduction of 2-'ch1oromethyl-3-nitropropene-l1which comprises reacting, at a temperature of not more than about 100-C., methallyl-chloridein an aqueous medium with nitrous acid which isgenerated within the aqueous medium.

55 A process [for the production of 1-nitro-'2- chloromethyl 4,4dimethylpentene-z] which comprises reacting, at a temperature of. notmore thanabout100 C., 2-ch1oromethy1-4,4-dimethy1- DBntene-I with anitrogen oxide.

6. Aprocess [for 'theproduction of1-nitro 2-j chloromethyl 4,4dimethyIpentene-Z] which comprises reacting, at a temperature of notmore than'about 100 0., 2chloromethyl-4,4-dimethylpentene-l in anaqueous medium with nitrous acid.

7. [1 nitro 2- chloromethyl 4,4-dimethyipentene-ZJ 8. A process [for-theproduction of l-nitro-Z- chloromethyl e-chiorobutene-fl which comprisesreacting, at a temperature of not more than about 100 0.,Z-chloromethyl-A-ch1or'obu= tene lwith anitrogen' oxide.

9. A-processlffor the production of 1-nitro-2- chloromethyl4-=ch1orobutene21 which com= prises reacting, at a temperature of notmore than about 100 C., 2-ehloromethyii -chlorobu tene-l in an aqueousmedium with nitrous'acid.

10. [1 nitro 2 chlorcmethyl 4-ch1orobutens-2.]

11. [A 3 -'ch1oro- Z-aikylidene-l-nitroa1kane containingfrom 4 to 16carbon atoms] 12. A process [for the production of 3-ch1oro-2'-a.1ky1idene-l-nitroalkanes] which comprises reacting, at atemperature of not more than about (halogen)Oy -CN Or 14. A process forthe production of monoolefinic-mononitroha1ohydrocarbons which com-:prises reacting at a temperature of not more than about 100 C. amono-olefinic halohydrocarbon having from 4 to 16 carbon atoms to themolecule and which contains the structural grouping OH (haJogen)C- (I):C with a, nitrogen oxide.

15. The mcno-olefinic mononitrohalohydnocarbon produced by "the processdefined in claim 2.

16. The mono-olefinic mononitrohalohydrocarb-on produced by the processdefined in claim 5.

17. The mono-olefimc mononitrohalohydrocarbon produced by the processdefined in claim 9.

18. The mono-olefim'c mononitrohalohydrocarbon prodnced'by the processdefined in claim 12. 19. The mono-olefinzc mononitrohalohydrocar bonproduced by the process defined in claz'mlsl.

EDUARD CORNELIS KOOIJMAN. JOHAN OVERHOFF.

REFERENCES CITED The'follo-wing references'are of record in the file ofthis patent or the original patent:

Science News Letter. March 22,1947, page 188.

